Chronic neuroleptics alter the effects of the D1 agonist SK&F 38393 and the D2 agonist LY171555 on oral movements in rats.

Journal Article (Journal Article)

Vacuous oral movements (OMs) in rats chronically administered haloperidol (HAL), fluphenazine (FLU), or no drug were studied following injections of one of three doses of either a D1 agonist (SK&F 38393) or a D2 agonist (LY171555). Oral movements were observed via closed-circuit television and simultaneously recorded using a computerized video analysis system which measured the distance between two fluorescent dots painted above and below the rat's mouth. SK&F 38393 induced a dose-dependent increase in tremorous oral movements and repetitive chewing movements in the controls; this effect was more pronounced in rats treated with chronic HAL or FLU, both during chronic neuroleptic treatment and even more so when they were tested after drug withdrawal following 5 or 14 months of chronic neuroleptic administration. Conversely, LY171555 produced an inhibition of oral activity at all dose levels in controls. This inhibition was attenuated during chronic administration of HAL or FLU, but returned to control levels (without any signs of supersensitivity) when the animals were retested shortly after discontinuation of neuroleptics. These results indicate that heightened oral movements in rodents following chronic neuroleptic administration can be more clearly induced by D1 than by D2 receptor activation.

Full Text

Duke Authors

Cited Authors

  • Ellison, G; Johansson, P; Levin, E; See, R; Gunne, L

Published Date

  • 1988

Published In

Volume / Issue

  • 96 / 2

Start / End Page

  • 253 - 257

PubMed ID

  • 2906749

International Standard Serial Number (ISSN)

  • 0033-3158

Digital Object Identifier (DOI)

  • 10.1007/BF00177570


  • eng

Conference Location

  • Germany